When to replace drivers?

Hi all,

I am currently pending purchase of a pair of used Dunlavy speakers, and would like some feedback from this community if possible about the following:

Is there some rule (general, opinion, or otherwise) as to the age of drivers, and when to replace them?

IE: If a speaker is over 10 years old, other criteria? Any feedback would be greatly appreciated, I'm trying to "do this right the first time".

Thank you!
Over 10 years doesnt really mean that they will need work, I would ofcourse say they are alot closer to needing re-foam than new, but visual inspection and listening to them will be the very first step, then report your findings for helpful replies, I know I didnt help much but I think it is too early to tell or worry, hope you enjoy your new purchase! best regards Chad
>>When to replace drivers?

When they're broken!
Most speakers take hundreds of hours to break-in.
If they sound good, keep 'em.
If the surrounds or cones are bad, get them fixed.
Never replace a driver in one speaker without doing it in pairs if your budget allows.